Modeling question - twist/bend part of a mesh
Great method for shapes like that is shown here in the picture. Here is what you have to do: 


place 3 profile (can be more) meshes depending on what form you want. Profiles must have the same vertex count.
join all the parts into 1 mesh.
with profiles selected press W and then 'Bridge edge loops'.
check 'Tools menu (T)' for more options if you need. 
apply subdivision modifier.




You can see the result in the second picture. This is similar. For your case you must adjust the placement of the profiles and then adjust the 2nd. profile to match the one you need. I think you will need 4 profiles to get an accurate result.